Table 2: Main approaches to laboratory diagnosis.


Direct microscopyRespiratoryLow costInsensitive, labour intensive
CultureRespiratory, tissueLow cost, enables further analysisInsensitive
HistopathologyTissueEnables proven diagnosisRequires biopsy tissue
Galactomannan (GM)Serum, BALSensitive, specimens easy to obtainLacks sensitivity in patients on antifungals
β-D-glucan (BDG)SerumSensitive, specimens easy to obtainLacks specificity
PCR (DNA detection)AnySensitive, can be applied to any specimenLabour intensive, expensive